Rocket motor thrust control system



July 16, 1968 L. w. GOLDBERG ROCKET MOTOR THRUST CONTROL SYSTEM Original Filed July 9,

2 Sheets-Sheet 1 AGENT July 16, 1968 L. w. GOLDBERG ROCKET MOTOR THRUST CONTROL SYSTEM Original Filed July 9,

INVENTOR. ZZOYD M 6010564 6 AGENT United States Patent ROCKET MOTOR THRUST CONTROL SYSTEM Lloyd William Goldberg, Clifton, N.J., assignor to Thiokol Chemical Corporation, Bristol, Pa., a corporation of Delaware Original application July 9, 1962, Ser. No. 208,216, now Patent No. 3,258,915, dated July 5, 1966. Divided and this application Mar. 1, 1966, Ser. No. 530,843

11 Claims. (Cl. 239-26535) This application is a division of application Ser. No. 208,216 filed July 9, 1962, now Patent No. 3,258,915 and entitled Rocket Motor Thrust Control System.

The present invention relates to jet propulsion motors and in particular to an apparatus or device for thrust control thereof. The principal object of the invention is to provide an improved means for thrust control in a jet propulsion motor wherein the motor nozzle or portions theref are movable to provide said thrust control.

In carrying out the object of the present invention a jet propulsion motor is provided having a nozzle which includes flexible members. Upon actuation of said members, motor. thrust, as represented by a thrust vector, undergoes a positional change such that a turning moment is applied to. the vehicle containing the jet propulsion motor. A further object of the invention is to provide a jet propulsion motor having a movable throat in the nozzle thereof which is capable of being moved by an externally mounted actuating means to effect a lateral displacement of said thrust vector, thereby inducing a turning moment about the center of gravity of the vehicle containing the motor. A still further object of the invention is to provide a jetpropulsion motor wherein downstream portions of the motornozzle are flexibly connected to the remainder of the motor and are actuated by externally mounted-means so as to provide an angular and/0r lateral displacement of the thrust vector to induce a turning moment of the vehicle about its center of gravity.

Other objects of the invention will be pointed out in thefollowing description and claims and illustrated in the accompanying drawings, which disclose by way of examples, the principle of the invention and the best mode, which. has been contemplated, of applying that principle.

In the drawings:

' FIGURE 1 is a schematic elevational view of a type of jet propulsion motor for which the present invention is adapted showing the general location of flexible parts.

FIGURE 2 is a section of the motor taken along the lines 2-2 of FIGURE 1.

FIGURE 3 is a second schematic elevational view of the invention in a somewhat different version and is illustrative of its important features.

FIGURE 4 is a rearward perspective view of a missile showing an actuation means wherein a variation in thrust vector displacement is obtained in conjunction with the invention of FIGURE 3.

Referring to FIG. 1 there is shown a form of the invention wherein it is adapted for installation in a jet propelled vehicle such as an airplane, missile or the like. The invention as set forth in FIG. 1 consists of a rocket or jet motor having inner and outer shells 11 and 12 respectively, and a moveable throat 14 mounted between a flexible member such as cylindrical bellows 13, and a second flexible member such as conical bellows 15. Flexible members 13 and form structural parts of motor- 10'being extensions of inner liner 11 and expansion cone 16. Connection of bellows 13 to shell liner 11 and to movable throat 14 is accomplished by any manner well known to those skilled in the art, as for example, by welding'as shown in the drawings.

3,392,918 Patented July 16, 1968 Shellsll and 12 are representative of the usual arrangement in the regeneratively cooled liquid propellant rocket motor construction art wherein two, essentially concentric, shells are constructed so as to permit the passage therebetween of a cooling fluid. In the usual practice, the cooling fluid is one or more of the liquid propellants which are thereafter combusted within the confines. of the motor, although a separate coolant such as water may be employed. The former arrangement is contemplated herein for illustrative purposes, but should not be construed as limitative thereto.

When constructed as described herein, throat 14 is usually formed as shown, with entrance and exit having larger diameters than the intermediate sections so as to present to the gases passing therethrough a relatively smooth and contoured path whereby the gases may be accelerated through the motor. Since throat 14 is in effect suspended between the flexible members 13 and 15, movement thereof relative to the remainder of motor 10 is readily accomplishable. Therefore, attached to throat 14 and to the flying vehicle structure 17, shown in outline in FIGURE 1 for illustrative purposes, is an actuating means consisting of a piston containing hydraulic cylinder 18, connecting rod 19 and swivel connectors 20 and 21 attached to throat 13 and body 17 respectively, for that purpose. FIGURE 2 shows a typical installation wherein a system of three such piston containing cylinders 18 are used to effect movement of throat 14 in any of three directions, or a combination thereof.

FIGURE 3 is illustrative of a second embodiment of the invention, wherein the usual jet propulsion motor 10 comprises inner and outer shells 11 and 12, a throat 22 and an expansion nozzle or exit cone 23. Expansion nozzle or exit cone 23 is connected to the throat 22 by means of a flexible member or conical bellows 24, and to outer shell 12 by a second flexible member of cylindrical bellows 25. Similarly to the invention of FIG. 1, the space between shells 11 and 12 is provided for passage therethrough of cooling fluid, usually one of the propellants in liquid propellant rocket engines. In this embodiment actuating cylinders 18 (one shown) are again mounted to body 17 by connectors 21. Attachment to motor 10 is accomplished through connectors 20 and rod 19. However, vehicle body 17 is provided with an annular end piece or bearing plate 26 having a smooth faced surface 27. Connecting link 28 is equipped with a fiat sided follower 29, which through suitable pin attachment is adaptable to contact bearing plate 26 in a hereinafter described restraining manner.

In a manner similar to the invention of FIG. 1, wherein throat 14 was in effect suspended between bellows 13 and 15, expansion cone 23 is suspended between flexible elements or bellows 24 and 25. As will be shown in what follows, flexible members or bellows 24 and 25 in cooperation with actuating cylinder 18 permit a lateral shift (FIG. 2) or in cooperation with cylinders 18a and 18b permit an angular displacement (FIG. 4 of cone 23 which results in a corresponding shift in thrust or of the thrust vector representative thereof.

The invention herein described has particular application, but is not limited, to a jet propulsion motor of the type wherein thrust is produced by the expulsion of high speed gases from the interior thereof, being useful in any system wherein thrust vector control is desirable. In the usual case gases are produced by the combustion of propellants in a motor chamber. Propellants are usually one of the so-called solid or liquid type. For illustrative purposes the latter type wherein an oxidizer enters a chamber, such as defined by shell 11, at 0, through orifice 30, together with a fuel (after being conducted through the space between shells 11 and 12 by means of pipe F) 3 through orifices 31, ignited and burned. The gases thus produced are accelerated in the motor and expelled at high speed from expansion orexit cones 16 (FIG. 1) and 23 (FIG. 3 and FIG. 4).

In the device of FIG. 1 when actuating cylinder 18 through its contained hydraulic pressure extends connecting rod 19, a displacement or shift of throat 14 through a finite distance x, occurs. This shift results in a transverse deflection of the motor thrust (or a portion thereof) as represented by thrust vector TV (solid arrow, FIG. 1), to a new position T V (dash arrow, FIG. 1). Deflection or shift of the thrust vector results in the development of a turning moment acting on the flying vehicle containing the motor which is equal to theshifted thrust T V multiplied by the distance x, since the undeflected thrust vector TV, as is the usual practice, passes through the vehicle center of gravity (C.G. inFIGS. 1 and 3).

In the FIG. 3 arrangement the same, or similar, result with respect to the thrust vector TV, is obtained. However, in this latter embodiment, upon actuation of any one of the piston containing actuating cylinders 18, expansion or exit cone 23 is caused to move in cooperation with flexible members or bellows 24 and 25, bearing plate 26, and flat sided follower 29, in a direction transverse to themotor and/or vehicle 17 longitudinal axis through a distance x. Expansion cone 23 is restrained from any move ment except a translation normal to the axis abovementioned by angular mounting of actuating cylinders 18, which urge expansion cone 23 forwardly against the direction of the exiting gases. In addition, follower 29, which is provided with a flat surface of sufficient area in contact with bearing plate surface 27 helps to prevent any other movement. Follower 29 may also be equippedwith bearings (not shown) for relatively freer movement over surface 27. Thus, a similar turning moment substantially equal to the shifted or deviated, thrust vector T V (dash arrow, FIG. 3), multiplied by the distance x is developed, and acts upon the vehicle. Control of the vehicle is therefore limited by the length of stroke ofrod 19 of cylinders 18 of which a minimum of two are required for all manner of movement over the plane of bearing plate surface 27. Of course, as a practical consideration, the actual number is determined by the space available within the vehicle.

In FIG. 4 a still further embodiment is shown wherein double acting cylinder 18a and 18b (minimum twoin number) are mounted on missile or vehicle 17 by means of universal connectors 35 and attached to expansion cone 23 such that cone 23 is restrained from movement in a rearward direction, being forced or biased against extensible two-way cushion mount 32 through postsor abutments 33 and mounting connectors 34. Two-way cushion mounts 32 are capable of acting so as to contract or elongate depending on the manner of loading and are cooperaitve with cylinder 18a and 18b and bellows 24 and 25 to eflect an angular displacement of cone 23. For instance, if one or both of cylinders 18a or 18b is actuated, cone 23 pivots about the longitudinal axis through an angle A (FIG. 4) to provide control of thrust thereabout. As illustrated in FIG. 4 with no angular displacement of expansion cone 23 the thrust of motor 10, represented by thrust vector TV, acts along the longitudinal axis of the vehicle 17 in accordance, usually with design requirements of the system. Cylinders 18a and 18b as shown are mounted on vehicle 17 and cone 23 at right angles to each other, hence actuation of one cylinder causes a responsive, cooperative action on the part of the other such that practically any preselected angular displacement of cone 23 can be achieved by properly actuating the cylinders either singly or together. As an example, if cylinder 18a is extended, cone 23 will pivot accordingly and thrust vector TV will pivot through an angle A to new position T V to provide a moment about vehicle 17 C.G. equal to T V times the displacement distance x. It is evident that by proper control of actuation cylinder 18a and 18b, which are double acting, that all angular displacements are possible within the limits determined by the length of stroke of pistons contained by cylinders 18a and 18b.

While there have been shown, described and pointed out the fundamental and novel features of the invention as applied to two preferred embodiments, it will be underst-ood that various omissions, substitutions and changes in the form and details of the device illustrated and in its operation may be made by those skilled in the art, without departing from the spirit of the invention. It is the intention, therefore, to be limited only as indicated as the scope of the following claims.

What is claimed is:

1. A thrust control device for a nozzle containing jet propulsion motor operative to propel a flying vehicle by the thrust developed from the rearward expulsion of high speed gases from said motor nozzle comprising, an inner shell having a throat section, a first flexible member communicably connected to said throat section in said nozzle, an expansion cone communicably connected to said first flexible member in said nozzle, an outer shell substantially concentric with said inner shell, a second flex-ible member connecting said outer shell to said expansion cone, a bearing plate fixedly attached to said vehicle surrounding said expansion cone, swivelling means on said expansion cone contacting said bearing plate, and an actuating means mounted on said vehicle and attached to said cone comprising a piston containing fluid pressure operated cylinder for displacing said expansion cone with respect to the longitudinal axis of said motor for effecting a displacement of at least a portion of said thrust produced by said motor to create a turning moment on said vehicle about its center of gravity.

2. The thrust control device of claim 1 wherein the actuating cylinder is swivelled on said body and operatively directed to oppose a rearward elongation of said rocket motor.

3. The thrust control device of claim 1 wherein the actuating cylinder is double acting. I

4. A thrust control device for a nozzle containing jet propulsion motor operative to propel a flying body comprising, a throat section in the nozzle, an expansion cone in said nozzle, at least one flexible member mounted in said nozzle between said throat and said expansion cone, and an actuating means attached to said flying body and to said expansion cone, said actuating meanscomprising a pair of fluid pressure operated actuating cylinders arranged about the periphery of said flying body so as to form an angle of at least between the points of attachment thereon, an annular bearing plate attached to said flying body surrounding said expansion cone, a plurality of force responsive, expansible cushion mounts fixedly attached to said bearing plate and a plurality of abutting posts attached to said expansion cone swivelly contacting said mounts for transmitting forces developed by said actuatingcylinders, said actuating cylinders, said mounts, said abutting posts and said flexible members, cooperative to effect an angular displacement of said expansion cone with respect to said longitudinal axis of said flying vehicle to create a turning moment on said body about .its center of gravity.

5. The thrust control device of claim 4 wherein the pair of actuating cylinders are swivel mounted and operatively directed so as to oppose a rearward elongation of said rocket nozzle.

6. The thrust control system of claim 4 wherein the actuating cylinders are double acting.

7. A thrust control device for a nozzle containing jet propulsion motor mounted in a flying body comprising, a throat section in the nozzle, a flexible member attached to said throat section and downstream thereof, an expansion cone attached to said flexible member and downstream thereof, an actuating means comprisin a pair of fluid pressure operated cylinders mounted on said flying body and on said expansion cone so as to oppose a rearward movement of said expansion cone said cylinders mounted on said flying body periphery having an angle of 90 therebetween, a bearing plate attached to said flying body surrounding said expansion cone, a plurality of equiangularly positioned cushion mounts attached to said bearing plate and a plurality of abutting posts swivelled on said expansion cone each contacting a cushion mount on said bearing plate for transmitting forces developed by said hydraulic cylinders to said mounts, said hydraulic cylinders cooperative with said flexible member, said mounts, said posts to eflect an angular displacement of said expansion cone about the longitudinal axis of said flying body.

8. A thrust control device for a nozzle containing jet propulsion motor operative to propel a flyin vehicle by the thrust developed from the rearward expulsion of high speed gases from said motor nozzle comprising, an inner shell having a throat section, a first flexible member commun-icably connected to said throat section in said nozzle, an outer shell substantially concentric with said inner shell, a second flexible member connecting said outer shell and said expansion cone, a bearing plate fixedly attached to said vehicle surrounding said expansion cone, means on said expansion cone slidably contacting said bearing plate, and an actuating means mounted on said vehicle and attached to said cone comprising a fluid pressure operated cylinder for transversely displacing said expansion cone with respect to the longitudinal axis of said motor for effecting displacement of at least a portion of said thrust produced by said motor to create a turning moment on said vehicle about its center of gravity.

9. A thrust control device for a nozzle containing jet propulsion motor operative to propel a flying body comprising a throat section in the nozzle, an expansion cone in said nozzle, at least one flexible member mounted in said nozzle and between said throat and said expansion cone, and an actuating means attached to said flying body and to said expansion cone, said actuating means comprising a pair of fluid pressure operated actuating cylinders arranged about the periphery of said flying body so as to form an angle of at least between the points of attachment thereon, an annular bearing plate attached to said flying body surrounding said expansion cone, sliding means comprising a follower contactably movable over said bearing plate attached to said cone, said follower being moved in response to forces developed by said cylinders, said sliding means, said flexible members and said cylinders arranged to effect a transverse displacement of said expansion cone with respect to said longitudinal axis of said body to create a turning moment on said body about its center of gravity.

10. The thrust control device of claim 9 wherein the actuating cylinders are swivelled on said body and operatively directed to oppose a rearward elongation of said nozzle.

'11. The thrust control device of claim 9 wherein the actuating cylinders are double acting.

References Cited UNITED STATES PATENTS 3,032,982 5/1962 Gaubatz 239265.35 3,090,198 5/1963 Zeisloft 239-265.35 3,140,584 7/1964 Ritchey et a1. 239265.35 3,179,447 4/1965 Parr et al 239265.35 3,182,452 5/1965 Eldred 239265.35 3,184,917 5/1965 Caouette et al. 239265.35 3,251,553 5/1966 Fittoh et al. 239-26535 3,258,915 7/1966 Goldberg 239265.35 3,270,505 9/1966 Crabill et al. 239-26535 EVERETT W. KIRBY, Primary Examiner, 

1. A THRUST CONTROL DEVICE FOR A NOZZLE CONTAINING JET PROPULSION MOTOR OPERATIVE TO PROPEL A FLYING VEHICLE BY THE THRUST DEVELOPED FROM THE REARWARD EXPULSION OF HIGH SPEED GASES FROM SAID MOTOR NOZZLE COMPRISING, AN INNER SHELL HAVING A THROAT SECTION, A FIRST FLEXIBLE MEMBER COMMUNICABLY CONNECTED TO SAID THROAT SECTION IN SAID NOZZLE, AN EXPANSION CONE COMMUNICABLY CONNECTED TO SAID FIRST FLEXIBLE MEMBER IN SAID NOZZLE, AN OUTER SHELL SUBSTANTIALLY CONCENTRIC WITH SAID INNER SHELL, A SECOND FLEXIBLE MEMBER CONNECTING SAID OUTER SHELL TO SAID EXPANSION CANE A BEARING PLATE FIXEDLY ATTACHED TO SAID VEHICLE SURROUNDING SAID EXPANSION CONE, SWIVELLING MEANS ON SAID EXPANSION CONE CONTACTING SAID BEARING PLATE, AND AN ACTUATING MEANS MOUNTED ON SAID VEHICLE AND ATTACHED TO SAID CONE COMPRISING A PISTON CONTAIING FLUID PRESSURE OPERATED CYLINDER FOR DISPLACING SAID EXPANSION CONE WITH RESPECT TO THE LONGITUDINAL AXIS OF SAID MOTOR FOR EFFECTING A DISPLACEMENT OF AT LEAST A PORTION OF SAID THRUST PRODUCED BY SAID MOTOR TO CREATE A TURNING MOMENT ON SAID VEHICLE ABOUT ITS CENTER GRAVITY. 